<!DOCTYPE html>
<html lang="zh-CN">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta http-equiv="X-UA-Compatible" content="ie=edge" />
    <title>Document</title>
  </head>

  <body>
    <div id="app">
      <h2>总价格：{{totalPrice}}</h2>
    </div>

    <script src="../js/vue.js"></script>
    <script>
      const app = new Vue({
        el: '#app',
        data: {
          books: [
            {
              id: 110,
              name: 'Unix编程艺术',
              price: 119
            },
            {
              id: 111,
              name: '代码大全',
              price: 105
            },
            {
              id: 112,
              name: '深入理解计算机原理',
              price: 98
            },
            {
              id: 113,
              name: '现代操作系统',
              price: 87
            }
          ]
        },
        computed: {
          totalPrice: function () {
            let sum = 0
            for (const i of this.books) {
              sum += i.price
            }
            return sum
          }
        }
      })
    </script>
  </body>
</html>
